This invention relates to microelectronic circuit cases, and in particular to a new and improved ground connection.
Microelectronic components such as chips, substrates and other devices are packaged in a variety of configurations. One widely used technique is to mount the circuit component in a metal case with a plurality of feedthrough conductors in the form of terminals or leads individually positioned in insulators in a wall of the case. A lid is attached to the case to provide a hermetic enclosure. The cases come in a variety of sizes, typically ranging from about 0.4 to 0.4 inches to about 2 by 4 inches, with thecase interior in the order of 1/8 inch deep.
The standard case is a metal container, being drawn from a single piece of metal or being assembled with a bottom and four sides. The circuit component or components are mounted in the case with electrical connections to appropriate leads, and the lid is attached. A typical metal case and method for seam welding a lid thereto are shown in U.S. Pat. No. 4,015,071.
Often it is desired to have one or more of the leads of a case electrically grounded. In the past, this has been accomplished by utilizing a metal for sealing the lead in the case, rather than an insulator. This provides a satisfactory ground connection, but has a serious disadvantage in that the specific lead to be grounded has to be decided prior to the manufacture of the case.
It is an object of the present invention to provide a new and improved microelectronic circuit case which may be conventional in construction and which may be modified after completion of the case for grounding of any one or more of the leads. A further object is to provide such a grounding connection by means of a flat plate or clip which can be attached to an outer wall of the case and to a selected lead, by conventional spot welding, brazing or the like.
Further objects, advantages, features and results will more fully appear in the course of the following description.